There have been numerous designs of trench drains and floor drains over the years. These are typified by U.S. Pat. Nos. 5,529,436 (owned by the assignee of the present disclosure), 6,027,283, and 6,612,780. However, there remain certain disadvantages with such drains, particularly in the labor and expense required in initially forming and assembling the trench drain components prior to casting concrete around them for installation and use, and further, because the trench frame sections need to be directly connected to one another, i.e. joined end-to-end. The latter requirement prevents, in effect, any random placement of drains at separate locations. Additional problems with some trench drains include the needed levelling of one given section relative to an adjacent section, the need to frame up the trench drain for the pouring of concrete, and the need to assure the trench drain stays in place, i.e. does not float, while the concrete is being poured.
Additionally, there have been drains where an underlying drainage conveyance was formed to have no top portion, i.e. such a drain had an elongated opening in the top of the drainage conveyance when the latter was created, and a drain grate structure was associated with that opening. Such elongated opening-type drains are typified by U.S. Pat. Nos. 3,815,213; 4,490,067; 5,380,121; and 5,908,266. However, these prior elongated-opening drain devices had disadvantages. For example, they do not permit the grate structure (which usually sits atop the lower elongated-opening conveyance) to directly transmit loads placed on such grates to the surrounding concrete or earthen support structure. Instead, such grate-developed loading forces are placed directly on the underlying conveyance structures, causing them to be weakened. Further, some such prior devices require very convoluted and configured extrusion or injection molding designs, i.e. to create the interconnected upper surface grate and lower elongated opening drainage conveyance structure. Thus they are often costly, both from a mold-making and molding standpoint. They also do not permit use of a detachable drain grate member, for periodic removal of the drain grate to allow for any needed cleaning of the underlying drainage conveyance through the elongated opening.